1. Field of the Invention
The invention generally relates to distributed printing, wherein printers with different capabilities can be effectively combined to print documents including pages having different device-specific properties, such that some of the pages must be printed on a printer of a first type and other pages must be printed on a printer of a second, different, type. More in particular, the invention relates to a method of printing such documents, based on automatically analyzing the data of the print job with respect to device-specific properties of its pages and designating each page, on the basis of the analysis, either for processing on a printer of the first type or for processing on a printer of the second type.
2. Discussion of the Related Art
One example of device-specific properties of pages is the existence of colour in some of the document pages, while other pages contain only black-and-white image elements. Such print jobs cannot be completely printed on a black-and-white-only printer without losing image information. One solution would be to use a colour printer. A colour printer would be able to print such a print job in its entirety, but colour printers are generally slower and more expensive to use. Another possible solution would be to split the print file into a colour-containing part and a black-and-white-only part, and print each part on an appropriate printer. This may be cost-effective and may increase processing speed, but it requires that the user himself split the print file in two parts, and after printing merges the prints into one print set, which takes great precision and is error-prone.
This problem may be partly solved by a method known from U.S. Pat. No. 5,978,557, which discloses a system that checks every page of a print job for the presence or absence of colour, and automatically sends pages containing colour to a colour printer and pages not containing colour to a monochromatic (i.e. black-and-white) printer. Flag sheets are inserted in the monochrome print set to indicate the places where colour prints are to be inserted. Although this known method saves a user the effort of splitting a print file into parts, this method takes over control of the process from the user who cannot choose the printers used for the job any more and, moreover, still leaves him with extra work of merging the prints from the different printers later.